The invention relates to a housing for encasing a nozzle, particularly an air covering nozzle or an air texturing nozzle, with at least one filament pass-through aperture having a filament pass-through aperture circumference and a housing cover that covers a housing opening in a housing base, the housing cover engaging with housing base ridges on the housing base by means of cover ridges. A housing of such kind is referred to as a soundbox and is used in yarn processing machines particularly to deaden the operating noise produced by the nozzle.
Yarn processing machines with an air covering nozzle (air covering machine) are used to combine filament yarns in a resilient, multi-component yarn (air covering yarn). In this process, the components of at least one sheath yarn (effect yarn) are combined with a core yarn. The objective of this process is to achieve the most uniform connection nodes possible in the multi-component yarn, and thus to combine the components. An example of an air covering machine is disclosed in U.S. Pat. No. 6,405,519 B1. The core filament is usually a yarn containing an elastomer. The sheath filaments may include various effect yarns. The filament yarns, that is the sheath yarns and the core yarn, are fed to an air covering nozzle via drawing mechanisms, e.g. godets. After the multi-component yarn has passed through the air covering nozzle, it is collected on a spindle, round which the yarn is wound. Before being wound, the multi-component yarn may be stretched, fixed, shrunk and/or scrooped. In the air covering nozzle, the sheath filaments are combined with the core filament with the aid of an air jet. For this, the air jet is directed in a direction that is not parallel to an air covering nozzle axis of the air covering nozzle. The air covering nozzle axis of the air covering nozzle is defined by a channel in which the filament yarns are guided through the air covering nozzle. According to the prior art, at least the core filament is guided into the air covering nozzle parallel to the air covering nozzle axis via a filament feed guide. Ideally, the sheath filaments are also guided into air covering machines with an infeed direction that is at least approximately parallel to the air covering nozzle axis.
Yarn processing machines for processing filament yarns with an air texturing nozzle (air texturing machine) are also known. Such an air texturing machine is disclosed in German Patent No. DE 39 09 516 A1. Air texturing machines are used to crimp smooth, unstructured filament yarns to lend them resilience. Multiple base yarns (core yarns) may be worked together with effect yarns of various origins to create a textured yarn. Unlike an air covering machine, the filament yarns in air texturing machines are always fed into the air texturing nozzle with feed directions that form an acute angle with an air texturing nozzle axis, i.e. into a channel of the air texturing nozzle that defines the axis of the air texturing nozzle, through which the filament yarns are passed. Ideally, the infeed direction of the effect yarns forms a right angle with the infeed direction of the core yarns, the air texturing nozzle axis forming a 45 degree angle with the infeed directions of both the effect yarns and the core yarns.
The nozzle, that is to say the air covering nozzle of the air texturing nozzle of a yarn processing machine of such kind, is mounted in a housing. The housing both protects the nozzle and damps the operating noises that are created when the nozzle is in operation. Known housings including filament pass-through apertures in a base of the housing and a housing cover. The housing cover protects a housing opening in the housing base, and the housing cover is attached to ridges in the housing base by ridges in the cover. The cover enables work on the nozzle and/or other assemblies mounted in the housing to be carried out through the housing opening. In addition, the filaments to be processes, that is to say the core filament and the sheath filaments, must be guided through the filament pass-through apertures so that they reach the nozzle. The filaments must also be fed to the nozzle with the housing cover open, since the respective yarn end must be seized for this purpose inside the housing. In order to achieve the greatest possible insulation within the housing, the filament pass-through apertures must be very narrow. Accordingly, feeding the filaments through these apertures is very time-consuming, and must be carried out with the aid of a special suction nozzle. As a consequence, the known housings are associated with substantial production losses while the filaments are being fed into the housing.
The task underlying the present invention is to provide a housing for enclosing a nozzle that not only avoids the drawbacks of the prior art but particularly enables rapid feeding of the filaments to be processed.